HI in the galaxies not only serves as the reservoir of material for forming stars in the future, but also provides an advtantageous tracer of kinematical properties. The HI group uses HI as a useful tool to understand galaxy evolution, and is currently focusing on gas accretion, the circular and non-circular motion of the HI gas, and the environmental effects. They actively combine the information drawn from the HI data with those from the other bands, and believe that this multi-wavelength reactions lead to marvellous discoveries.